https://bugs.kde.org/show_bug.cgi?id=357059

            Bug ID: 357059
           Summary: x86: SSE cvtpi2ps with memory source does transition
                    to MMX state
           Product: valgrind
           Version: 3.10.0
          Platform: Gentoo Packages
                OS: Linux
            Status: UNCONFIRMED
          Severity: normal
          Priority: NOR
         Component: vex
          Assignee: jsew...@acm.org
          Reporter: janne-...@jannau.net

Valgrind does a transition to MMX state on cvtpi2ps with memory source operand
which can't be observed on various CPUs (tested on Haswell, Core2 Duo, AMD K8,
at least).

According to Intel's Instruction Reference Manual from September 2015
Valgrind's behaviour is correct. A ancient version from 1999
(http://www.c-jump.com/CIS77/reference/Intel/CIS77_24319102/pg_0162.htm)
however describes the observed behaviour.

For cvtpi2pd the observed behaviour is actually documented, see bug #210264 and
vex commit r1961.

I'm not 100% sure valgrind should deviate from the documentation so a
clarification from Intel or AMD would be helpful.

Reproducible: Always

Steps to Reproduce:
1. gcc -o cvtpi2ps_test cvtpi2ps_test.c
2. valgrind ./cvtpi2ps_test

Actual Results:  
prints "cvtpi2ps caused a transition to MMX state"

Expected Results:  
prints nothing

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